[jira] [Commented] (HADOOP-7401) Unit test TestPureJavaCRC32 warmup code warms up the not-so-important loop in PureJavaCRC32.update()

["Hadoop QA (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HADOOP-7401?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13051336#comment-13051336 ] 

Hadoop QA commented on HADOOP-7401:
-----------------------------------

-1 overall.  Here are the results of testing the latest attachment 
  http://issues.apache.org/jira/secure/attachment/12482990/HADOOP-7401.patch
  against trunk revision 1136249.

    +1 @author.  The patch does not contain any @author tags.

    -1 tests included.  The patch doesn't appear to include any new or modified tests.
                        Please justify why no new tests are needed for this patch.
                        Also please list what manual steps were performed to verify this patch.

    -1 patch.  The patch command could not apply the patch.

Console output: https://builds.apache.org/job/PreCommit-HADOOP-Build/649//console

This message is automatically generated.

> Unit test TestPureJavaCRC32 warmup code warms up the not-so-important loop in PureJavaCRC32.update()
> ----------------------------------------------------------------------------------------------------
>
>                 Key: HADOOP-7401
>                 URL: https://issues.apache.org/jira/browse/HADOOP-7401
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: test
>    Affects Versions: 0.21.0
>         Environment: Solaris-Sparcv9; Solaris-AMD64
>            Reporter: monica beckwith
>            Priority: Minor
>             Fix For: 0.21.0
>
>         Attachments: HADOOP-7401.patch
>
>   Original Estimate: 1m
>  Remaining Estimate: 1m
>
> When the warmup code sequence in TestPureJavaCRC32.java is executed, it sends size=len=2 and due to the value of 'trials' in for loop in doBench(), the crc.update() gets run > the compile threshold, thus providing the information that 'while 0<len<7' is a hot loop and 'while len>7' is a cold loop. This brings the MB/s number for len > 7 in PureJavaCRC32.update() way down (e.g. ~28.5% for size=len=65536).
> The workaround would be to use size=len=>7 (so just having size=len=2101 ahead of size=len=2 will do the trick) in the warmup section. 

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira